Steve Griffin, head of the MacDuffie School in Granby, says the students were struck while sitting outside at a picnic table on Tuesday afternoon.

He told The Daily Hampshire Gazette that two students were knocked unconscious while a third suffered less serious effects. Griffin said a 16-year-old victim had no pulse when three faculty members performed CPR at the scene.

“It was amazing how quickly they responded and I think they contributed to how this girl has recovered,” Griffin said. “I understand that she has been released from the hospital which is great news. We’re relieved.”

MacDuffie is a coeducational school with about 200 students in grades 6 through 12, about half whom are boarders.